JPH0760974A - Method of manufacturing ink jet device - Google Patents

Abstract

(57) [Summary] [Purpose] When a piezoelectric ceramic member is injection-molded, the part corresponding to the driving part of the piezoelectric ceramic should not be damaged. A sublimable substance 96 is placed at a predetermined position in a mold, a material to be a piezoelectric ceramic member is injection molded from a gate 81, insert molded into a piezoelectric ceramic member molded body, and a mold plate 92 and a mold plate. After opening 83 and moving the eject pin 84 in the direction of arrow 85 to release the piezoelectric ceramic member compact and the sublimable substance 96 from each other, the sublimable substance 96 is removed from the piezoelectric ceramic member compact by sublimation. Therefore, the piezoelectric ceramic having a fine shape is not damaged.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention has a piezoelectric ceramic member provided with a drive section that is deformed by applying a voltage and a plurality of ink flow paths that apply pressure to ink by the deformation of the drive section. The present invention relates to a method for manufacturing an ink jet device.

[0002]

2. Description of the Related Art Conventionally, as an ink jet device of this type, there is one described in, for example, Japanese Patent Laid-Open No. 2-150355. A conventional example of the schematic configuration will be described below with reference to FIG.

As shown in FIG. 4, the ink jet printer head 1 is composed of a piezoelectric ceramic plate 2, a cover plate 3, a nozzle plate 31, and a substrate 41.

A plurality of grooves 8 are formed on the piezoelectric ceramic plate 2 by cutting using a thin disk-shaped diamond blade or the like. The side wall 11 which is the side surface of the groove 8 is polarized in the direction of arrow 5. The grooves 8 are of the same depth and are parallel. The depths of the grooves 8 are the one end surface 15 of the piezoelectric ceramic plate 2.
The shallow groove 16 is formed in the vicinity of the one end surface 15. Then, on the inner surface of the groove 8, metal electrodes 13 are formed on the upper half of both side surfaces by sputtering or the like. The metal electrode 9 is formed on the inner surface of the shallow groove 16 on the side surface and the bottom surface by sputtering or the like. As a result, the metal electrodes 13 formed on both side surfaces of the groove 8 are connected by the metal electrodes 9 formed in the shallow groove 16.

Next, the cover plate 3 is made of a ceramic material, a resin material, or the like. Then, the cover plate 3 is formed by grinding or cutting.
An ink inlet 21 and a manifold 22 are formed. Then, the surface of the piezoelectric ceramic plate 2 on the side where the groove 8 is processed and the surface of the cover plate 3 on the side where the manifold 22 is processed are bonded by an epoxy adhesive or the like. Therefore,
The ink jet printer head 1 has a plurality of ink flow paths 1 which are covered with the upper surfaces of the grooves 8 and are laterally spaced from each other.
2 is configured. Ink is filled in all the ink flow paths.

To the end faces of the piezoelectric ceramic plate 2 and the cover plate 3, a nozzle plate 31 having a nozzle 32 provided at a position corresponding to the position of each ink flow path 12 is adhered. The nozzle plate 31 is made of a plastic such as polyalkylene (for example, ethylene) terephthalate, polyimide, polyetherimide, polyetherketone, polyethersulfone, polycarbonate, or cellulose acetate.

A substrate 41 is adhered to the surface of the piezoelectric ceramic plate 2 opposite to the processed side of the groove 8 with an epoxy adhesive or the like. Its substrate 41
The conductive layer pattern 4 at the position corresponding to each ink flow path.
2 is formed. The pattern 42 of the conductive layer and the metal electrode 9 on the bottom surface of the shallow groove 16 are connected by a conductive wire 43 by wire bonding.

In the ink jet device having such a structure, the first
In order to cut the piezoelectric ceramic plate 2,
There have been problems that microcracks are generated in the piezoelectric ceramics to shorten the life of the head, and the surface roughness of the ceramics is deteriorated to cause adverse effects on electrode formation.
Secondly, since the nozzle plate 31 in which the nozzle 32 is formed is adhered to the end faces of the piezoelectric ceramic plate 2 and the cover plate 3, the position of the nozzle 32 formed in the nozzle plate 31 and the piezoelectric ceramic plate 2 Since the position of each nozzle 32 corresponding to each ink flow path is determined by the position of the nozzle plate 31 bonded to the end surface of the cover plate 3, the position accuracy of each nozzle 32 corresponding to each ink flow path is poor. problem,
In addition, when the nozzle plate 31 is bonded, the surplus adhesive flows into the inner surface of the nozzle 32, which disturbs the straightness of the ink when ejecting the ink and causes the nozzle 32 to be clogged.

In order to solve this problem, the present applicant has filed Japanese Patent Application Nos. 4-324275 and 4-324276.
I am proposing an issue. Japanese Patent Application No. 4-324275 is intended to solve the first problem by forming a piezoelectric ceramic member by injection molding. Japanese Patent Application No. 4-324276 discloses that a piezoelectric ceramic member and a nozzle are integrally formed by an injection molding method.
The second problem is to be solved. However, in the ink ejecting apparatus having such a configuration, since the ink introducing port 21 and the manifold 22 are formed in the cover plate 3, the shape of the cover plate 3 becomes complicated and control in cutting becomes complicated. There is a problem in that manufacturing takes time and mass productivity is poor.

Therefore, the applicant of the present invention filed Japanese Patent Application No. 5-7654.
I am proposing an issue. In Japanese Patent Application No. 5-7654, at least one of the ink inlet 21 and the manifold 22 and the piezoelectric ceramic plate are integrally formed by injection molding.

[0011]

However, Japanese Patent Application No. 4-324275, Japanese Patent Application No. 4-324276,
And according to the method as shown in Japanese Patent Application No. 5-7654,
As shown in FIG. 5, a piezoelectric ceramic member including a driving portion that is deformed when a voltage is applied is formed by injection molding.
Since the driving unit of this type of ink ejecting apparatus is extremely fine, after injection molding material is introduced from the gate 81 and injection molding is performed, the mold plate 82 and the mold plate 83 are opened, and the eject pin 84 is moved to the arrow 85 direction. When the piezoelectric ceramic member molded body moves in the direction and is released from the mold plate 82, a portion corresponding to the driving portion of the piezoelectric ceramic member molded body remains in the mold,
There is a problem that the piezoelectric ceramic member molded body is damaged.

Further, according to the method described in Japanese Patent Application No. 4-324276, there is a problem that not only the driving portion but also the nozzle portion is damaged.

The present invention has been made to solve the above-mentioned problems, and provides a method of manufacturing an ink ejecting apparatus in which a piezoelectric ceramic member molded body is not damaged when the piezoelectric ceramic is manufactured by injection molding. The purpose is to do.

[0014]

In order to achieve this object, in the method of manufacturing an ink jet device of the present invention, when a material to be a piezoelectric ceramic member is injection-molded in a mold, a sublimable substance is added to the metal. It is installed at a predetermined position in the mold and insert-molded into the piezoelectric ceramic member molded body, and after the molded body is released from the mold, the sublimable substance is removed from the piezoelectric ceramic member molded body by sublimation. Characterize.

[0015]

According to the method of manufacturing an ink ejecting apparatus of the present invention having the above-mentioned structure, the sublimable substance insert-molded in the piezoelectric ceramic member molded body is removed by sublimation from the piezoelectric ceramic member molded body. Does not damage the piezoelectric ceramic member molded body.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A method of manufacturing an ink jet printer head, which is one embodiment of the present invention, will be described below with reference to the drawings. For convenience, the same parts as those of the conventional example and the equivalent parts are designated by the same reference numerals, and the description thereof will be omitted.

First, the calcined piezoelectric ceramic powder and a binder such as a thermoplastic resin, wax, or plasticizer are kneaded.

As the thermoplastic resin, polyethylene, polypropylene, polystyrene, ethylene-vinyl acetate copolymer, polyacrylic acid, polyacrylic acid ester, polymethacrylic acid, polymethacrylic acid ester and the like can be used.

As the wax, natural waxes such as beeswax, carnauba wax, wood wax, paraffin wax and microcrystalline wax and synthetic waxes such as polyethylene glycol, montan wax derivative, paraffin wax derivative and microcrystalline wax derivative can be used. .

As the plasticizer, diethyl phthalate, dibutyl phthalate, dioctyl phthalate, fatty acid esters and the like can be used.

In addition to the above binder, a lubricant such as stearic acid may be added.

The ratio between the piezoelectric ceramic powder and the amount of binders added is usually 50:50 to 60: 40% by volume.
Is.

In the present embodiment, 90% by weight of lead zirconate titanate powder, which is the piezoelectric ceramic powder calcined at 850 ° C., 5% by weight of polymethacrylic acid ester, which is the thermoplastic resin, and the wax are used. Paraffin wax 2% by weight and microcrystalline wax 2
% By weight and 1% by weight of the plasticizer, dioctyl phthalate, are weighed and kneaded with a pressure kneader for 2 hours.

The method of kneading the piezoelectric ceramic powder and the binders is not particularly limited, and they may be kneaded with a Banbury mixer or the like.

After the kneading, the kneaded product is made into pellets by a pelletizer, and the pellets serve as a raw material for injection molding.

The kneaded product does not necessarily have to be pelletized by a pelletizer, but may be granulated by a pulverizer.

Next, a sublimable substance having a sublimation point higher than the injection temperature (about 140 ° C.) is cut with a diamond blade to form a shape corresponding to the groove 8 and the side wall 11 (FIG. 4). As the sublimable substance, naphthalene, cresol, aminophenol, saccharin, salicylic acid, anthraquinone and the like can be used. Further, a mixture of these sublimable substances with a small amount of a polymer resin material may be used for the purpose of supplementing the strength. The width of the groove 8 was 100 μm, and the depth of the groove 8 was 600 μm.

Then, as shown in FIG. 1, the groove 8 and the side wall 1 are formed.
The sublimable substance 96 having a shape corresponding to 1 is placed in the mold.

Next, the injection molding raw material is put into an injection molding machine and filled through the gate 81 at an injection pressure of 700 kgf / cm ² , and the piezoelectric ceramic molded body is insert-molded. At this time, since the sublimable substance 96 has a sublimation point higher than the injection temperature, it does not sublime during injection molding.

Then, the mold plate 92 and the mold plate 83 are opened, the eject pin 84 is moved in the direction of the arrow 85, and the sublimable substance 96 and the piezoelectric ceramic molded body are released from the mold together. At this time, the mold release resistance does not act on the portions corresponding to the fine-shaped groove 8 and the side wall 11, so that the portion is not damaged.

As the injection molding machine, an ordinary resin injection molding machine or a ceramics or metal injection molding machine having improved wear resistance is used.

Then, the piezoelectric ceramics compact and the sublimable substance 96 are placed in a degreasing furnace and subjected to a degreasing treatment for removing the organic material such as the thermoplastic resin and the sublimable substance contained in the piezoelectric ceramics compact. . On this occasion,
The degreasing furnace contains an inert gas such as argon and nitrogen, a reducing gas such as hydrogen, or a combustion-supporting gas such as oxygen and air. is there. Further, the inside of the degreasing furnace may be in a reduced pressure state.

The temperature of the degreasing treatment in this embodiment is 50 ° C./hour from room temperature to 120 ° C. and 10 ° C./hour from 120 to 160 ° C.
160 to 200 ° C., 4 ° C./hour, 200 to 350 ° C., 5 ° C./hour, 350 to 450 ° C., 10 ° C./hour, 450 to 5
00 ° C. is 50 ° C./hour, and the temperature inside the degreasing furnace is sequentially increased.

In the degreasing furnace, if the temperature is raised from room temperature to an arbitrary temperature of 500 to 600 ° C. at about 2 to 100 ° C./hour,
The temperature may not be raised as described above.

After that, the furnace is cooled to form a degreased body of piezoelectric ceramics. At this time, compressed air is introduced from the gas inlet of the degreasing furnace by the air compressor. And
This compressed air is discharged from the gas discharge port of the degreasing furnace together with the thermoplastic resin and other organic materials removed from the piezoelectric ceramic molded body.

Next, the degreased piezoelectric ceramic body from which the thermoplastic resin and other organic materials have been removed is placed in an atmospheric sintering furnace and sintered.

In the present embodiment, the temperature in the air sintering furnace is raised from room temperature to 1200 ° C. at 150 ° C./hour, and the temperature is 1200 ° C.
After being held for 2 hours, the temperature is lowered to 700 ° C at 300 ° C / hour. Then, the furnace is cooled to form the piezoelectric ceramic plate 2 which is a piezoelectric ceramic sintered body. The width of the groove 8 of this piezoelectric ceramics sintered body is 8 due to sintering shrinkage.
It becomes about 5 μm, and the depth of the groove 8 becomes about 500 μm.

In the atmosphere sintering furnace, the room temperature is 900 to 1
As long as the temperature is raised to an arbitrary temperature of 400 ° C. and kept at the raised temperature for about 0 to 2 hours, it is not necessary to raise the temperature as described above.

Then, after the piezoelectric ceramic plate 2 thus formed is polarized, metal electrodes 13 and metal electrodes 9 as shown in FIG. 4 are provided in the same manner as in the conventional example, and the grooves 8 of the piezoelectric ceramic plate 2 are processed. The surface on the side and the cover plate 3 are adhered to form a plurality of ink flow paths 12, and the nozzle plate 31 is adhered to the end surface of this joined body to form the substrate 4
By connecting the pattern 42 of the first conductive layer and the metal electrode 9, it is possible to manufacture an inkjet printer head having the same configuration as the conventional example.

As described above, according to the manufacturing method of this embodiment, a sublimable substance is used for the mold of the side wall 11 having a fine shape in the piezoelectric ceramic plate, and the mold is removed by sublimation after injection molding. The piezoelectric ceramic plate will not be damaged during release.

The present invention is not limited to the embodiments described in detail above, and modifications can be made without departing from the spirit of the invention.

For example, in the present embodiment, only the side wall 11 which is the driving portion is formed on the piezoelectric ceramic plate 2, but as shown in FIG. 2, when the nozzle 30 is integrally formed, it is sublimable. After forming the substance in a shape corresponding to the ink flow path 8 and the nozzle 30, insert molding may be performed as in the above-described embodiment. By doing so, it is possible to easily manufacture an ink ejecting apparatus in which the accuracy of the position where the nozzle is formed is good, the surface roughness and shape of the inner surface of the nozzle are good, and the printing quality is good.

Furthermore, as shown in FIG. 3, the piezoelectric ceramic plate 2 is provided with an ink inlet 21 and a manifold 22.
When the and are integrally formed, the sublimable substance may be formed into a shape corresponding to the ink flow path 8, the ink introduction port 21, and the manifold 22, and then insert-molded. By doing so, the shape of the cover plate is simplified and mass productivity is excellent. In this case, only the ink introduction port 21 is integrally formed with the piezoelectric ceramic plate 2, and the manifold 22 is provided on the cover plate 3 side, or only the manifold 22 is integrally formed with the piezoelectric ceramic plate 2, and the ink introduction port 21 is covered. It is also possible to make a change such that it is provided on the plate 3 side.

The sublimable substance is not limited to those exemplified in the above examples, and any substance may be used as long as it has a sublimation point higher than the injection temperature and has a certain strength as an injection molding die. It is available even if there is.

[0045]

As is apparent from the above description, according to the present invention, a piezoelectric ceramic member including a driving portion that is deformed when a voltage is applied is injection-molded into a mold by using a material for the piezoelectric ceramic member. When the sublimable substance is placed at a predetermined position in the mold and insert-molded into the piezoelectric ceramic member molded body, and the molded body is released from the mold, the sublimable substance is removed from the piezoelectric ceramic member molded body. Is removed by sublimation, the drive unit having a fine shape is not damaged. Further, since the nozzle can be formed integrally with the piezoelectric ceramic member, the accuracy of the position where the nozzle is formed is good, the surface roughness and shape of the inner surface of the nozzle are good, and the printing quality is good. Can be easily manufactured. Further, since it is possible to integrally form at least one of the ink introduction port and the manifold on the piezoelectric ceramic member, the shape of the cover plate is simplified and the mass productivity is excellent.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a configuration of a piezoelectric ceramic plate injection molding die according to an embodiment of the present invention.

FIG. 2 is a perspective view of an inkjet printer head according to another embodiment of the present invention.

FIG. 3 is a perspective view of an inkjet printer head according to another embodiment of the present invention.

FIG. 4 is a perspective view showing a configuration of an inkjet printer head of the present invention and a conventional example.

FIG. 5 is a cross-sectional view showing the configuration of a conventional piezoelectric ceramic plate injection molding die.

[Explanation of symbols]

 2 piezoelectric ceramic plate 8 groove 11 side wall 21 ink inlet 22 manifold 32 nozzle 83 type plate 92 type plate 96 sublimable substance

Claims (4)

[Claims] 1. A method of manufacturing an ink ejecting apparatus having a piezoelectric ceramic member, comprising: a drive unit that is deformed by applying a voltage; and a plurality of ink flow paths that apply pressure to ink by the deformation of the drive unit. In, when injection-molding a material to be the piezoelectric ceramics member in a mold, a sublimable substance is placed at a predetermined position in the mold and insert-molded into a piezoelectric ceramics member molded body, and the molded body is A method for manufacturing an ink ejecting apparatus, which comprises releasing the sublimable substance from the piezoelectric ceramic member molded body after releasing from the mold. 2. The method of manufacturing an ink ejecting apparatus according to claim 1, wherein the sublimable member is installed at a position corresponding to each of the plurality of ink flow paths. 3. The piezoelectric ceramic member includes an ink introduction port for introducing ink from an ink supply source, and a manifold communicating with the ink introduction port and filling the introduced ink into the plurality of ink flow paths. 2. The method for manufacturing an ink ejecting apparatus according to claim 1, further comprising integrally forming at least one of the ink inlet and the manifold and the piezoelectric ceramic member by injection molding. 4. The piezoelectric ceramic member is provided with a nozzle for ejecting ink droplets by the deformation of the drive unit, and the nozzle and the piezoelectric ceramic member are integrally formed by injection molding. 1. The method for manufacturing the ink ejecting apparatus according to 1.